#include<stdio.h>
#include<math.h>
int main()
{
	double a,b;
	double c;
	scanf("%lf %lf",&a,&b);	
	c=a+b/10;
	c=c/1.9;
	int y;
	y=(int)floor(c);
	printf("%d",y);       
 return 0;
}	